Expression and Function of Recombinant S1179D Endothelial Nitric Oxide Synthase in Canine Cerebral Arteries

Background and Purpose— Bovine endothelial nitric oxide synthase (eNOS) is phosphorylated directly by the protein kinase Akt at serine 1179. Mutation of this residue to the negatively charged aspartate (S1179DeNOS) increases nitric oxide (NO) production constitutively in the absence of agonist stimulus. The present study was designed to determine the effect of mutant S1179DeNOS gene expression on vasomotor function of canine cerebral arteries. Methods— Isolated basilar and middle cerebral arteries were exposed ex vivo (30 minutes at 37°C) to an adenoviral vector (1010 plaque-forming units per milliliter) encoding the S1179DeNOS gene (AdCMVS1179DeNOS), the wild-type eNOS gene (AdCMVeNOS), or the green fluorescent protein (GFP) reporter gene (AdCMVGFP). Twenty-four hours after transduction, arteries were suspended in an organ chamber for isometric force recording, and levels of cGMP were measured by radioimmunoassay. Results— Transgene protein expression was detected mainly in the vascular adventitia. In Ad...